Conventionally, equipment for the cleaning of the inside of tanks and similar containers are mounted on a down-pipe coming through the top of the tank. The equipment comprises a down-pipe, which extends into the tank and on which there is mounted cleaning equipment. The cleaning equipment is connected to a piping system for the supply of cleaning fluid. The supply of cleaning fluid to the cleaning head rotates the cleaning head since the cleaning head is provided with slots through which the cleaning fluid is guided and the design of the slots creates the rotational movement. The cleaning fluid lays fans in a swirling pattern throughout the tank.
This type of cleaning equipment is normally used for the cleaning of tanks when they are empty. By the design of the slots of the cleaning head different spray patterns can be achieved, e.g. 360°, 270° up or 180 down. The equipment can be mounted either in a permanent manner or it can be mounted when taken into use. By the flow of cleaning fluid through the cleaning equipment, the cleaning equipment is self-cleaned.
One example of the above mentioned cleaning equipment is the SaniMidget Rotary Spray Head from Alfa Laval, where the rotary spray head includes a connector part for connecting to the down-pipe and a rotor part, rotatable arranged on the connector part. The connector part is connected to the down-pipe by a spring clip. Rotor part or rotating head is fitted into the connector part and welded onto a rotor part. The rotor part is resting on a number of balls (the bearing surface). This is a non-dismountable design due to the welding.
Another cleaning device is known from US-B2-7 063 274, where a cleaning nozzle is disclosed, where the nozzle includes a nozzle body arranged between a bearing element and a securing element, and where the nozzle body is rotatably supported by the bearing element and the securing element. The nozzle body can be secured either by screwing the bearing element onto the securing element or by having a spring plug to secure the bearing element onto the securing element.
The problem with the prior art solution is that the design of them does not fulfill the 3A requirements of a hygienic design, stating that a cleaning device should be possible to dismount and that it should not be completely cleanable and without possible non-cleanable spaces.